CLOSED DRUG DELIVERY SYSTEM

Abstract: An apparatus for controllably intermixing two or more components in a sterile, closed environment to produce a flowable substance and then for expelling the flowable substance from the apparatus at a precisely controlled rate. The apparatus is particularly useful for medical applications and includes a dispenser portion (804) with its own stored energy element provided in the form of an elastomeric membrane (992) and a coupling mechanism (807) for coupling a drug vial (820) to the dispenser (804) for controlled mixing of medicament (877) contained within the drug vial (820) with a diluent (832) stored within the dispenser portion of the apparatus via a sterile pathway.

Description: CLOSED DRUG DELIVERY SYSTEM S P E C I F I C A T I O N Background of the Invention Field of the Invention - The present invention relates generally to fluid mixing and delivery systems. More particularly, the invention concerns an apparatus for intermixing selected medicaments to form a flowable substance and for then infusing the substance into a patient at a precisely controlled rate. Discussion of the Invention Medicament delivering systems that can separately store and then controllably intermix a selected medicament with a diluent for infusion into a patient at a controlled rate have come into wide use. In the prior art systems the diluent is generally packaged in flexible plastic containers having admin¬ istration ports for connection to an administration set which delivers the container contents from the container to the pa¬ tient. The drug is often packaged in a separate, closed con¬ tainer and is mixed with the diluent shortly before infusion of the medicament in the patient. Drugs are typically packaged separately from the diluent for a number of reasons. One important reason is that certain drugs do not retain their efficacy when mixed with a diluent and, therefore, the mixture cannot be stored for any appreciable length of time. Another reason is that many drug manufacturers do not produce medical fluids in containers for intravenous delivery. As a general rule, drugs are packaged in powder form in small, closed containers, or vials, for later mixing with a suitable diluent. In many instances it is neces- sary to mix the drug with the diluent immediately prior to delivery to the patient to insure that the drug will not sepa¬ rate from the diluent prior to or during infusion. Infusion of medicaments is most often accomplished in a hospital environment and the nurse, doctor or other medical personnel mixes the drug and diluent shortly before administra¬ tion of the drug to the patient. This mixing step can be time consuming and hazardous, as for example, when toxic drugs are used. Additionally, many of the prior art mixing devices are crude and imprecise making accurate, sterile and thorough mixing of the drug and the diluent difficult, time consuming and not well suited for use in the home environment. Several types of closed drug delivery systems are presently in use. These systems typically comprise a flexible container such as a plastic bag to which a drug vial can be coupled. The flexible container usually contains a liquid diluent and often includes a frangible member that allows fluid passage only when broken. When the drug vial is coupled with the flexible container, the stopper of the drug vial is pierced and the frangible member ruptured so as to allow sterile commu¬ nication between the drug vial and the liquid diluent contents of the flexible container. Mixing of the drug with the diluent is accomplished by manipulating the flexible container. Exem¬ plary of prior art systems of the aforementioned character are those disclosed in U.S. Patent No. 4,583,971 issued to Bocquet, et al. and in U.S. Patent No. 4,606,734 issued to Larkin. Another prior art closed delivery and mixing system is disclosed in U.S. Patent No. 4,458,733 issued to Lyons. The Lyons apparatus includes a compressible chamber with a " liquid component therein, the compressible chamber including gas- trapping and reservoir compartments in open communication. The gas trapping compartment can be connected to a container such as a drug vial having a mixing component therein. After a pathway between the vial and the gas trapping compartment is opened, mixing is accomplished through manipulation of the compressible chamber. Another very successful prior art, dual container system is described in U.S. Patent Nos. 4,614,267 issued to Larkin and 4,614,515 issued to Tripp and Larkin. In this system, a flexible diluent container includes a tubular port which provides means for securing thereto a stoppered medica¬ ment vial as well as a stopper removal means. The stopper removal means includes an engagement element, or extractor, which is attached to a removable cover and seals the inner end of the port. In use, as the vial is advanced into the tubular port, the vial stopper moves into engagement with the extractor which grips the stopper enabling it to be pulled from the vial as the cover is pulled from the port. Once the stopper has been removed from the vial, the contents of the vial can be dumped into the diluent in the bag and mixed therewith through manipulation of the bag. The prior art devices of the character described in the preceding paragraphs typically use the traditional gravity flow method for infusion of the medicament mixture into the patient. Such a method is cumbersome, imprecise and typically requires bed confinement of the patient. Also, the flexible bag must be maintained in a substantially elevated position and periodic monitoring of the apparatus by the nurse or doctor is required to detect malfunctions of the infusion apparatus. The apparatus of the present invention overcomes the drawbacks of the prior art by totally eliminating the need for a flexible bag, the cumbersome manipulative mixing of the medicaments using the flexible bag and the undesirable gravity infusion method which is typically followed when the flexible bag is used. As will be described in the paragraphs which follow, the apparatus of the present invention makes use of recently developed gas permeable elastomeric films and similar materials, which, in cooperation with a plate-like base define a fluid chamber that initially contains the first component, such as a diluent. Adjacent the base and in communication with the fluid chamber is a sterile coupling means for operably interconnecting a container such as a drug vial containing the second component. To enable controlled, sterile intermixing of the first and second components, the apparatus includes flow control means for controlling the flow of fluid through inter¬ nal passageways which interconnect the fluid chamber and the drug vial. The apparatus of the present invention is small, com¬ pact, easy to use and inexpensive to manufacture. The appara¬ tus provides a sterile, closed delivery system which can readi¬ ly be used by ambulatory patients and in home care environment. Connector elements are provided on the housing of the device which permits the apparatus to be conveniently affixed to the patient's clothing or to be strapped to the patients body. The apparatus of the invention can be used with minimal professional assistance in an alternate health care environment, such as the home. By way of example, devices of the invention can be used for intermixing numerous medicaments with suitable diluents and for the continuous infusion of medicament mixtures such as antibiotics, analgesics, hormonal, anticoagulants, clot dissolvers, immuno suppressants, and like medicinal agents. Similarly, the apparatus can be used for I-V chemotherapy and can accurately deliver fluids to the patient in precisely the correct quantities and at extended microinfu- sion rates over time. Summary of the Invention It is an object of the present invention to provide a compact, lightweight, low-profile apparatus for control¬ lably intermixing two or more components in a closed environ¬ ment to produce a flowable substance and then for expelling the flowable substance at a precisely controlled rate. More par¬ ticularly, it is an object of the invention to provide such an apparatus for medical applications which can be used in either a home care or hospital environment for the precise mixing and infusion of diluents and selected medicaments to an ambulatory patient at controlled rates over extended periods of time. It is another object of the invention to provide an apparatus of the aforementioned character which includes a dis¬ penser portion with its own stored energy means and coupling means for operably interconnecting a drug vial to the dispenser portion for controlled mixing of the medicament within the drug vial with a diluent stored within the dispenser portion via a sterile pathway. Another object of the invention is to provide an apparatus of the class described which permits extremely accurate fluid mixing and delivering, and one which is highly reliable and easy to use by lay persons in a non-hospital environment. Another object of the invention is to provide an apparatus which includes an internal fluid reservoir storage chamber that can be factory prefilled with a diluent or one which can readily be filled in the field shortly prior to use. Another object of the invention is to provide an apparatus of the character described in the preceding paragraph in which the reservoir is provided with an elastomeric energy source that can be subjected to gamma sterilization and extend¬ ed thermal sterilization temperatures without degradation of integrity and performance. Another object of the invention is to provide an apparatus in which intermixed fluids can be delivered to the patient either at a fixed rate or at precisely metered variable rates and one which is operational in all attitudes and al¬ titudes. Still another object of the invention is to provide an apparatus of the class described which includes means for securely interlocking the drug vial with the dispenser portion of the apparatus. Yet another object of the invention is to provide an apparatus as described in the preceding paragraph which is pro¬ vided with means for attaching the apparatus to the clothing of the patient or to the patients body. A further object of the invention is to provide a low profile, fluid delivery device of laminate construction which can be manufactured inexpensively in large volume by automated machinery. Another object of the invention is to provide a device of the character described in which fluid is dispelled from the apparatus through a cooperating infusion set by an expandable member cooperatively associated with a barrier membrane and a thin, plate-like base. Another object of the invention is to provide an apparatus of the aforementioned character in which the expandable member comprises an elastically deformable member having a cellular structure. Yet another object of the invention is to provide an apparatus of the class described in which a thin, planar filter element is disposed within the fluid chamber for filtering the reservoir outflow to the patient. Brief Description of the Drawings Figure 1 is a plan view of one form of the drug vial assembly of the present invention. Figure 2 is a cross-sectional view taken along lines 2-2 of Figure 1. Figure 3 is a generally perspective, exploded view of the container assembly of this last form of the invention. Figure 4 is a generally perspective view of various forms of adding means, or substrate assemblies, of this later form of the invention. Figure 5 is an enlarged, generally perspective ex¬ ploded view of still another embodiment of the invention. Figure 6 is an enlarged cross-sectional view of the embodiment shown in Figure 5 in an assembled configuration ready for use with the fluid reservoir in an uncharged configu¬ ration. Figure 7 is an enlarged cross-sectional view similar to Figure 6 but showing the fluid reservoir in a charged con¬ figuration. Figure 8 is an enlarged, generally perspective view of one of the blunt-end cannulas of the apparatus. Figure 9 is a generally perspective, exploded view of still another form of the invention. Figure 10 is an end view of the diluent container of the apparatus. Figure 11 is a cross-sectional view taken along lines 11-11 of Figure 10. Figure 12 is an enlarged cross-sectional view of the drug vial of the apparatus prior to being inserted into the coupling assembly of the apparatus. Figure 13 is an enlarged cross-sectional view of the embodiment shown in Figure 10 as it appears in an assembled configuration. Description of the Invention Turning to Figures 1 through 5, one embodiment of the invention is there shown. This embodiment of the invention comprises a cylindrical housing portion 800 and a base assembly 804. The embodiment also includes a highly novel stored energy source, the details of construction of which will presently be described. A distendable barrier member 992 engages and is moved by the stored energy source and this member also has a number of unique characteristics which will presently be de¬ scribed. Turning to Figure 4, various forms of additive carriers usable in this form of the invention are there illustrated. These additive carriers are disposed within the container assembly of the invention in the manner shown in the drawings so as to permit controlled intermixing of a first component such as a diluent, solvent or other parenteral fluid with an additive such as a medicament or other beneficial agent which is presented to the first component by the additive carriers which comprise a part of the adding means of the invention, the character of which will presently be described. In the paragraphs which follow, wherein the details of this unique intermixing process will be discussed, the following terms will have the following meanings: Element - any of the fundamental substances that consist of atoms of only one kind and that singly or in combination constitute all matter. Additive - the element, compound, substance, agent, biolog¬ ically active material, or other material which is to be added, all or in part, to the fluid introduced into the device of the invention. Polymer - a chemical compound or mixture of compounds formed by polymerization and consisting essentially of repeating structural units. Parenteral Fluid - any solution which may be delivered to a patient other than by way of the intestines, including water, saline solutions, alkalizing solutions, dextrose solutions acidifying solutions, electrolyte solutions, reagents, solvents and like acquous solutions. Beneficial Agents - any drug, medicament, pharmaceutical, medical polymer, enzyme, hormone, antibody, element, chemi¬ cal compound or other material useful in the diagnosis, cure, mitigation, treatment or prevention of disease and for the maintenance of the good health of the patient. Biologically Active Material - a substance which is biochemically, Immunochemically, physiologically, or pharmaceutically active or reactive. Biologically active material includes at least one or more of the following: biochemical compounds (such as amino acids, carbohydrates, lipids, nucleic acids, proteins, and other biochemicals and substances which may complex or interact with biochemical compounds) , such biochemical compounds biologically func¬ tioning as antibodies, antigenic substances, enzymes, co- factors, inhibitors, lectins, hormones, hormone producing cells, receptors, coagulation factors, growth enhancers, histones, peptides, vitamins, drugs, cell surface markers and toxins, among others known to those skilled in the art. Of the group of biologically active materials described, proteins are of utmost current interest because of the large molecule genetically engineered biopharmaceuticals as those species to be immobilized and congregated on the additive carriers hereinafter to be described. A discussion of the use of biomosaic polymers as carriers for biologically active materials is set forth in European Patent Application 0,430,517 A2. Adding Means - an additive and any means for presenting the additive to the fluid flowing through the fluid passageways of the fluid delivery device of the invention in a manner such that all or any part of the additive will be added to the fluid. The adding means comprises the additive and the additive presentation means which may take the form of a functional support, or carrier, an anchorage, a deposition or reaction site or an element holder with or without some type of intermediate matrix or other release composition. Additive Presentation Means - Any means such as a functional support or substrate for presenting the additive to the fluid flowing through the device. The functional substrate can comprise a polymer, copolymer, an inter-polymer, a ceramic, a crystal sponge, a carbon based matrix, a celullo- sic, glass, plastic, biomosaic polymers, azlactone-function- al polymer beads, adduct beads, carboxylate-functional polymer beads, gums, gells, filaments and like carriers. The adding means of the invention can take several different forms such as those illustrated in Figure 4. Howev¬ er, in its preferred form, the adding means comprises a cylin- drically shaped, microporous polymeric functional support structure which is disposed within the mixing chamber of the container assembly and to which various additives, including beneficial agents such as drugs, biologically active materials, and chemical elements and compounds can be releasably connect¬ ed. These additives are carried by the structure in a manner such that, as the liquid, such as a diluent, reagent, or other aqueous solvent flows around, about and through the support assembly in the manner shown by the arrows in Figure 2, the additives will be presented to the liquid flow and efficiently released and added to the liquid as it flows through the cham¬ ber which houses the adding means. The additives themselves can also take various physi¬ cal forms including liquid, solid, granular, powder, particle, gel, wax, hydrocolloid carrier, a gum, film, tablet, crystal¬ line, emulsions, microcrystalline, microspherical, spray dried compounds and lypohilized compounds and saturants. The addi¬ tives can be removably connected to, immobilized on, impregnat¬ ed within or supported by the support means in a number of ways. The additives can be chemically or mechanically at¬ tached, affixed, or bound directly or indirectly through coop¬ eration with an intermediate matrix. They can be captured, affixed, linked or cross linked, anchored to the surfaces of the support, or surface active agent, or they can be absorbed, reaction catalyzed, electrostatically encapsulated, attached by chemical modification in to the carrier surface, polymerized on or through the carrier, localized, entrapped, deposited, sus¬ pended or occluded within voids, cells, tubules, and intersti- cies formed in the support. One important method for removably affixing the additive to the functional support means includes treating the functional support means with a compound having reactive functional groups such as azlactone functional com¬ pounds with their high binding capacity. In certain applica¬ tions, the biologically active material can be bound at the surfaces of biomosaic polymers in the manner described in EPO Patent No. 0 430 517 A2. Similaraly, graft copolymers can be used in the manner described in U.S. Patent No. 5,013,795 issued to Coleman, et al. In this way complexing agents, catalysts and biological materials such as enzymes or other proteins as well as biomacromolecules can be attached to the carrier. Similarly, the additives can be immediately separated from the functional support and added to or intermixed with the liquid flowing through the device by one or more of various mechanisms, including chemical reaction, dissolution, debind- ing, delinking, displacement, bioseparation, diffusion, wash¬ ing, disintegration, errosion, dissassociation, desorbsion, solubilization, leeching, enzymatic cleavage, biological reac¬ tion, osmosis, separation from ring opening materials by a ring opening reaction and like separation means. As best seen in Figures 1 and 2, in the present form of the invention, cylindrical portion 800 is integrally con¬ nected to the back, concave surface 410 of the base member by means of suitable connectors. Portion 800 also includes a transversing extending base wall 807 having a socket 809 which supports a coupling member 812 in a manner best seen in Figure 2. Base 806 is provided with longitudinally extending passage¬ ways 814 and 816 (Figure 1) . Passageway 814 communicates with storage reservoir 832 and with port 815. Passageway 816 commu¬ nicates with the outlet port of the device formed in the outlet passageway housing 872. This passageway can also be used to aseptically prefill the reservoir during the manufacturing process. Similarly, a needle valve housing 874 extends angu¬ larly outwardly from back surface 410 and carries the second flow control means of the invention for controlling the flow of fluid through the fluid outlet of the base assembly. It is to be noted that the front surface of the base member is provided with crossing micro flow channels 812a and with an upstanding mounting boss 875 which surrounds port 815 to which a filter membrane 834 is bonded. Referring particularly now to Figure 3, the container assembly 820 of this form of the invention is there shown and comprises a glass vial 822 having a fluid flow passageway therethrough and walls defining a mixing chamber 824 in commu¬ nication with the fluid flow passageway. Chamber 824 functions to contain the adding means of the invention. A two-part plastic cover or overpackage 826 is closely received over vial 822. Cover 826 includes first and second portions 826a and 826b. Portion 826a is provided with external threads 830 and system interlock stops 831. Threads 830 are adapted to mate with internal threads 834b provided on cylindrical portion 800. Housed within vial 822 is the first flow control means of this form of the invention for substantially controlling the flow of fluid into and out of mixing chamber 824. Here the first flow control means comprises a plunger 836 sealably received within vial 822. Plunger 836 is generally cylindrical in shape and includes a skirt portion 838 adapted to sealably engage the inner wall of vial 822. Plunger 836 is provided with a centrally disposed bore 839 and a plurality of circumferentially spaced fluid passageways 840. An inlet or fine flow control valve member 842 also forms a part of the flow control means. Member 842 is reciprocally movable within bore 839 and is provided with a first flange portion 841 which functions to control fluid flow through passageways 840. Member 842 also includes a second or inboard flange 845 which guides the travel of the valve member within an annular channel 836a provided within plunger 836. Valve member 842 also includes a stem 847 which is disposed within a central flow passageway 842a and which, in a manner presently to be described, cooperates with a check valve 846 carried within an internal passageway 849 provided in coupling member 812 (Figure 3) . Stem 847 forms an integral part of the valve member 842 and terminates at an inboard end 847a. Prox¬ imate the opposite end of stem 847 is an enlarged diameter portion 847b which terminates in the previously identified flange 841. Extending angularly through portion 847b are circumferentially spaced fluid passageways 850 which, in a manner presently to be described, permit fluid flowing past check valve 846 to enter chamber 824 via passageway 850a. Turning particularly to Figure 2, the stored energy means of this latest form of the invention is shown as a flexi¬ ble elastic cellular mass, such as a sponge like polymeric foam member 990 and the barrier means which is acted upon by the member to expell fluid from the reservoir 832 is identified as deformable member 992. Expandable member 990, which is prefer¬ ably compressible, elastically deformable, and highly resil¬ ient, can be constructed from a wide variety of materials, including a number of flexible cellular polymers. Materials that are particularly attractive for this application include polyurethane, latex foam rubber, cellular rubber, foamed polym¬ ers, various polyolefin foams, PVC foams, epoxy forms, urea formaldehyde, silicon foam, fluropolymer foams, and other elastic syntactic foams, elastomers and similar materials of a character well understood by those skilled in the art. Member 990 can be monolithic or it can be constructed from homogeneous or nonhomogeneous foam or laminates having the same or differ¬ ent characteristics. In Figure 8, member 990 is shown in a substantially compressed state and ready to expand agains deformable barrier member 992 to urge the fluid containe within reservoir 832 outwardly from the device in a manne presently to be described. Barrier member 992 which may be a membrane, a film, a skin, or a laminate can also be constructed from a wide variet of permeable and nonpermeable materials including rubbers, plastics and other thermoplastic elastomers. These includ silicon polymers and high performance silicon elastomers. I is to be understood that member 992 can be separate from or interconnected with the outer interface of the energy source 990. In some instances, member 992 can be integrally forme with member 990 as a skin-like attachment and may exhibi elastomeric characteristics. In operating the apparatus of this latest form of th invention, the vial closure end cap 851 and the cap whic closes the socket or open end 809 of cylindrical portion 800 (not shown) are first removed. The open end of the drug vial assembly is then ready to be inserted into open end 809 of cylindrical portion 800. As the drug vial assembly is received within open end 809 of the infusion portion of the apparatus, threads 830 will move toward engagement with a first internal thread 834a provided within cylindrical portion 800. Rotation of the drug vial in a clockwise direction will cause the vial to advance within cylindrical portion 800 causing stem 847 to engage check valve 846. Because fluid under pressure within the reservoir resists movement of the check valve, operating valve 842 will move to the left. However, when flange 845 seats against internal shoulder 836a of plunger 836, continued clockwise rotation of vial 820 will cause stem 847 to move check valve 846 to the left into the open position shown in Figure 2. With the check valve in this open position, expanded member 990, which is in a compressed state will uniformly expand against barrier member 992 causing the fluid contained within chamber 832 to controllably flow under pressure through port 858a into passageway 858, then into circumferentially spaced passageways 849, past the valve seat 862 and into fluid passageway 846b of the coupling member. The fluid will then flow into passageway 850 and then vigorously into mixing cham¬ ber 824 via a central fluid passageway 850a formed in the adding means. It is to be appreciated that a polymer, a gel, or aduct bead can also be used as the carrier or support for the additive. Similarly, the second component which flows into chamber 824 can include, by way of example, a reagent, a solvent, a sterile diluent, various electrolytes, aqueous solutions such as aqueous solutions of dextrose, saline solu¬ tions, alkalinizing solutions, acidifying solutions, polar solutions and any other liquids that can serve as an appro¬ priate vehicle for the administration of therapeutic or benefi¬ cial agents which are desirable to administer to the patient by infusion. The various forms of adding means usable in this last form of the invention are illustrated in Figure 4. For example, numeral 880 identifies an assembly comprising an insoluble, polystyrene porous substrate having an axially extending fluid passageway 881 and interconnecting voids 880a interstitially of which one or more additives are releasably carried. The selected additives such as elements, chemical compounds, drugs and functional intermediates are provided on or within the voids by techniques well known to those skilled in the art. The additives are, of course, introduced into the elution agent such as a sterile diluent as the diluent flows round, about and through substrate 880. Another form of additive assembly designated in Figure 4 by the numeral 882, comprises a plugged pore substrate having an internal, axially extending fluid passageway 883. The pores of this alternate sized substrate releasably carry the additives such as time released chemical compounds and beneficial agents, or medicaments. Still another form of additive assembly is identified in Figure 4 by the numeral 884. This assembly comprises a cylindrical, porous plug like member made up of a multiplicity of fused together microspheres or beads 884a, each of which is coated with a separation or reactive coating upon which is deposited an additive such as a biologically active material or other beneficial agent. The microspheres which embody internal microchannels can be formed of glass, plastic or other suitable materials. The numeral 886 of Figure 4 identifies yet another form of the adding means of the invention. In this form of the invention a generally cylindrically shaped functional support serves as an affinity attachment for attachment and subsequent release of the additive. Support 886 has an axial fluid passa¬ geway 887 and is formed from a multiplicity of microporous polymers presenting a multiplicity of reactive sites over a wide area for species immobilization. The additive assembly designated in Figure 4 by the numeral 888 comprises a solid tubular member having an axial fluid passageway 889. The exterior surface of the member is coated with a selected additive by any suitable means including interfacial polymerization means with the use of an interpolym- er. Alternatively, member 888 can be constructed of an ion exchange resin material to which the additive, such as a drug can be bound, to provide a drug-resin complex of a charac¬ ter that permits the drug to later be controllably released over time when exposed to an appropriate elution fluid. Another slightly more complex additive assembly is identified by the numeral 890. This assembly is made up of a plurality of spaced apart, porous bung wafers 890a, 890b, 890c, and 890d, each wafer being of the same or different construc¬ tion and porosity and each having reactive sites presenting to the liquid flow specially selected additives such as beneficial agents, elements or compounds so that multiple reactivities and selectivities can be achieved. With this construction, a wide variety of liquid flow rates, and complex sequential separations and priority staged substance introduction into the system output can be achieved by specially designing each of the wafers that cooperate to make up the structural support. Still another form of activating assembly is desig¬ nated in Figure 4 by the numeral 892. This assembly comprises a cylindrically shaped structure made up of a plurality of elongated fibrous members 892a at least some of which are coated, pluged or impregnated with selected additives and, as necessary, functional intermediate materials. The functional support member identified by the numeral 894 exemplifies yet another form of adding means of the invention. This member, which is also of a generally cylindri¬ cally shaped configuration, is constructed from a plurality of discrete layers such as polymer films 894a onto which selected additives and intermediate compounds have been removably af¬ fixed. Functional support member 896 is constructed from a multiplicity of glass spaghetti-like strands 896a forming open cell, sponge-like construction, the cells of which are inter¬ connected by tortious interstitial flow paths. Some or all of the open cells carry the selected additive or additives de¬ sired. Functional support member 898 is constructed from a polymer foam which efficiently functions as the additive carri¬ er. It is to be understood that other forms of supports such as gells, biomosaic polymers and other porous forms of polymer reactive supports can be emplaced within mixing chamber 824 including joined azlactone-functional materials such as foams or polymer beads suitable for the attachment of function¬ al materials. Assemblies 880 through 898, which may be soluble or insoluble, hydrophillic or hydrophobic, are intended to merely exemplify, not to limit, the wide variety of materials and con¬ structions that can be used to present the desired additives to the liquid flow introduced into the mixing chamber of the device. As previously mentioned, the additives can be remov¬ ably affixed to the scaffolds, matrices or functional support means in various ways including the process of chemical modifi¬ cation of the matrix. One important manner of removably affix¬ ing the additives enables the use of special separation tech¬ niques broadly defined by the term chromotography. Chromotog- raphy as used herein refers to a group of separation techniques which are characterized by a distribution of the molecules to be separated between two phases, one stationary and the other mobile. Affinity chromotography involves the use of biological interactions and contemplates the use of affinity chromotogra¬ phy supports through which the eluting fluid flows. In the present embodiment of the invention, the various additive presentation means, as described herein, can assume the charac¬ ter of an affinity chromotography support to which various ligands are attached. In the practice of affinity chromotogra¬ phy techniques, one of the members of the pair in the interac¬ tion, the ligand, is immobilized on a solid phase, while the other, the counterligand (most often a protein) , is absorbed from the extract that is passing the substrate during the manufacturing process. Importantly, affinity chromotography techniques can include the use of highly versatile azlactone functional compounds, such as azlactone functional beads, as well as the use of a wide variety of other media for activation and coupling chemistry. Examples of ligands that can be at¬ tached to the affinity supports include antibodies, enzymes, lectins, nucleic acids hormones and vitamins. Examples of important counterligands include antigens, virus, cells, cell surface receptors and the like. Chromotography and affinity chromotography techniques are described in detail in Protein Purification by Janson and Ryden, Copyright 1989 and reference should be made to this work to provide a working understanding of the techniques. Polymeric azlactones are well known in the prior art. Their use in the production of homopolymers and copolymers has been described in a number of patents. See for example, U.S. Patent No. 3,488,327 (issued Jan. 6, 1970 to F. Kollinsky et al.); U.S. Patent No. 3,583,950 (issued June 8, 1971 to F. Kol¬ linsky et al.); U.S. Patent No. 4,304,705 (issued December 8, 1981 to S. M. Heilmann et al.); and U.S. Patent No. 4,737,560 (issued April 12, 1988 to S. M. Heilmann et al.); and " U.S. Patent No. 5,013,795 issued May 7, 1991 to Coleman, et al. Azlactones, or oxazolones, are cyclic anhydrides of N-acylamino acids and have been used extensively in organic synthesis. The formation of a five-membered azlactone of particularly useful functionality for immobilization purposes can be accomplished through the reaction of a carboxylate group with a-methyl alanine using a two-step process. (See Immo¬ bilized Affinity Ligand Techniques-Hermanson, Mallia and Smith, Copyright 1992) . One method of forming azlatone beads, the use of which has been previously mentioned herein, makes use of this process in the polymerization of monomers to first yield a carboxyl group on the matrix. In the second step, the azlac¬ tone ring is formed in anhydrous conditions through the use of a cyclization catalyst. Suitable cyclization agents that will drive this reaction include acetic anhydride, alkyl chlorofor- mates, and carbondiimides. The process of forming these active groups and of making beaded polymeric supports containing them has been thoroughly described in patents assigned to 3M Corpo¬ ration (U.S. Patent No. 4,871,824 and 4,737,560). These sup¬ port materials are now available under the tradename "Emphase". U.S. Patent Nos. 5,045,615 and 5,013,795 which have been as¬ signed to 3M Corporation also describe recent advances in this technology. As pointed out in the 3M Corporation Patent No. 4,737,560, azlactone-functional polymer beads are useful reac¬ tive supports for the attachment of functional materials to provide novel adduct beads. The adduct beads are useful as complexing agents, catalysts, reagents, and as enzyme or other protein-bearing supports. The term • ■ support" or "affinity support" as used in this sense is usually understood to refer to a combination of (1) a ligand (usually of some known molecu¬ lar configuration), that is firmly attached (e.g., immobilized) , often by covalent means, and (2) a matrix (usual- ly a solid insoluble substance) . Azlactone support matrix materials and coupling chemistry is also of special interest because of its accessible matrix surface area and effective ligand density that can be attached to that surface. U.S. Patent No. 4,072,566 issued to Lynn on February 7, 1978, and entitled "Immobilized Biologically Active Pro¬ teins" discloses a method of bonding enzymes or other biologi¬ cally active proteins to an inorganic support material using p- phenylenediamine. The support materials disclosed as useful in the invention include siliceous materials, stannic oxide, tita- nia, manganese dioxide, and zirconia. The functional support structure 877 of the present embodiment of the invention can take on the character of an affinity support and is uniquely constructed to permit enzymes or other biologically active proteins to be bound thereto for later removal. This is accomplished by treating functional support 877 in the manner disclosed in the prior art patents identified in the preceding paragraphs with a compound having selected reactive functional groups such as azlactone function¬ al compounds. In this way complexing agents, catalysts and biological materials such enzymes, proteins or other affinity absorbants, as well as biomacromolecules can be attached to the carrier for later removal and recovering. When attaching certain biologically active proteins and other macro molecules, the use of spacer arms or leashes have been found to be very beneficial. Spacer arms or leashes are low-molecular-weight molecules that are used as intermedi¬ ary linkers between a support material and an affinity ligand. Usually spacers consist of linear hydrocarbon chains with func¬ tionalities on both ends for each coupling to the support and ligand. First, one end of the spacer is attached chemically to the matrix using traditional immobilization chemistries; the other end is connected subsequently to the ligand using a secondary coupling procedure. The result is an immobilized ligand that sticks out from the matrix backbone by a distance equal to the length of the spacer arm chosen. Referring to Figures 5 and 6, another embodiment of the invention is shown. In this embodiment, the construction of the device is similar to that shown in Figures 1 through 4 and like numbers are used to designate like components. In this latest form of the invention the stored energy source once again comprises a unique sponge, foam or cellular type con¬ struction of the same character as member 990 of the last described embodiment. However, the vial assembly and the cylindrical housing portion are mated in a manner to mix the drug with the liquid component. The mixture thus produced charges the reservoir by distending the energy source which in this instance comprises compressible sponge member 990. Like the apparatus of the form of the invention just described, this embodiment also uniquely permits controlled intermixing of the first liquid component with the second component or additive such as a medicament or other beneficial agent which is pre¬ sented to the first component by the unique additive presenta¬ tion means, of the character defined in the preceding sections of this specification. In operating the apparatus of this latest form of the invention, the sterile vial closure caps 938 and 938a, which are provided at the ends of the vial 902 as well as a sterile closure cap which closes the open end of cylindrical portion 900 are first removed and discarded. As the drug vial assembly is received within open end 907 of portion 900, threads 923 will move toward engagement with threads 930a provided on housing body 908. Rotation of the drug vial in a clockwise direction will cause the vial to advance within cylindrical portion 900 causing cannula 927 to pierce elastomeric sealing member 926. After the drug vial assembly is fully seated, scalloped cap 938a, which is used to rotate the vial, is re¬ moved and discarded. With the drug vial assembly in place within cylindri¬ cal portion 900, the open end of liquid vial assembly 904 is inserted into an annular space 900a and threads 916 provided on cover or overpackage 915 are mated with internal threads 918a provided proximate the mouth of cylindrical portion 900. Rotation of assembly 904 will cause cannula 921 to pierce drug vial sealing member 925 in the manner shown in Figure 6 thereby opening fluid communication between chamber 914 of the diluent vial assembly and chamber 924 of the drug vial assembly. Continued rotation of the diluent vial assembly will cause threads 916 to move into an open annular space 942 there¬ by permitting the vial assembly to be forcibly pushed to the right from the position shown in Figure 6 to the position shown in Figure 7. This movement causes elastomeric plunger 920 to move to the left within chamber 914 thereby forcing the diluent D through cannula 921 and into the drug vial assembly under substantial pressure. The elution diluent will flow through glass frit 933 and then forcibly around, about and through support structure 937 of the adding means. The diluent flowing through glass frit 934 and into cannula 927 under pressure will cause check valve member 932 to move to the right into the open position shown in Figure 7 thereby permitting the fluid mixture to flow toward the reservoir 910 via passageway 909. " This fluid mixture flowing toward the reservoir will act on barrier member 992, which, in turn, will act upon compressible sponge 990 causing it to uniformly compress into the configuration shown in Figure 7. In its compressed state, expandable member 990 provides the energy source for controllably acting upon barrier member 992 to cause the fluid mixture to be control¬ lably expelled from the device in the manner previously de¬ scribed. Turning to Figures 9 through 13, still another em¬ bodiment of the invention is shown. In this embodiment, the construction of the device is similar to that earlier described and, once again, like numbers are used to designate like com¬ ponents. In this latest form of the invention, the distendable membrane once again acts as a barrier means for the energy source 990 which is of the character previously described. As before, vial assembly 954 can be mated with vial assembly 952 and with the cylindrical housing to mix the drug with the liquid component. With the unique construction of this last form of the invention, the liquid already within the prefilled reservoir can be controllably intermixed with the fluid within assembly 952 to form an infusible mixture which can be later discharged by the energy source or member 990. Stated another way, like the apparatus of the form of the invention just described, this embodiment permits controlled intermixing of the portion of the first liquid component or carrier component, contained within vial 954 with the second component or additive contained within vial 952 to produce a first mixture. This mixture of the carrier liquid and the additive can then be introduced into the reservoir which has been previously filled with a diluent or other liquid to pro¬ duce a second, injectable mixture for later infusion into a patient. In operating the apparatus of this latest form of the invention, the sterile vial closure caps 912a and 983b which close the ends of the vials 954 and 952 as well as a sterile closure cap which closes the open end of cylindrical portion 950 are first removed and discarded. As the drug vial assem¬ bly is received within open end 957 of portion 950, threads 975 will move toward engagement with threads 958a provided in base 958 proximate check valve housing 972. Rotation of the drug vial in a clockwise direction will cause the vial to advance within cylindrical portion 950 causing blunt end cannula 971 to pierce elastomeric sealing member 977b. With the drug vial assembly in place within cylindri¬ cal portion 950, cap 983a is removed and the open end of liquid vial assembly 954 is inserted into annular space 958a. Next, threads 966 provided on cover or overpackage 965 are mated with internal threads 968 provided proximate the mouth of cylindri¬ cal portion 950. Rotation of assembly 954 will cause cannula 971a to pierce drug vial sealing member 977a thereby opening fluid communication between chamber 964 of the liquid carrier diluent vial assembly and chamber 976 of the drug vial assem¬ bly. Continued rotation of the liquid carrier vial assem¬ bly will cause it to move to the right as viewed in Figure 13. This causes movement of elastomeric plunger 970 to the left within chamber 964 thereby forcing the carrier liquid or elu¬ tion diluent D through cannula 971a into the drug vial assembly under substantial pressure. The diluent will flow through glass frit 979 and then forcibly around, about and through scaffold matrices 982 of the adding means. The elusion diluent flowing under pressure through glass frit 980 and into cannula 971 will cause check valve member 962 to move to the right into the open position shown in Figure 13 permitting the fluid mixture to flow toward the reservoir 960 via passageway 959. This fluid mixture flowing toward the reservoir will control¬ lably intermix with the liquid component contained within the prefilled reservoir to form the infusible liquid mixture. In its compressed configuration, sponge member 990 provides the energy source for controllably expelling the infusible mixture from the device in the manner previously described. Venting of any gases contained within the stored energy means 990 can be accomplished through vents 444 (see Figure 6) . Similarly any gases contained in the reservoir can be vented through permeable deformable member 992 and to at¬ mosphere via vents 444. Having now described the invention in detail in accordance with the requirements of the patent statutes, those skilled in this art will have no difficulty in making changes and modifi¬ cations in the individual parts or their relative assembly in order to meet specific requirements or conditions. Such chang¬ es and modifications may be made without departing from the scope and spirit of the invention, as set forth in the follow¬ ing claims.

Claims: HE CLAIM 1. An apparatus for use in infusing fluids into a pa¬ tient at a controlled rate, said apparatus comprising: (a) a container assembly including: (i) a container having a fluid flow passageway and walls defining an internal chamber in communica¬ tion with said fluid passageway; (ii) adding means disposed within said chamber for adding an additive to fluid flowing through said chamber, said adding means comprising an additive and an additive presentation means for presenting said additive to the fluid; and (b) an infusion device comprising a housing having first and second portions, said first portion including coupling means for coupling said container assembly with said first portion of said housing, said coupling means having a first passageway adapted to communicate with said fluid flow passageway of said container, said second portion of said housing comprising: (i) a base having a fluid outlet and first and second fluid passageways formed therein, said first passageway being in communication with said first passageway of said coupling means and said second passageway being in communication with said fluid outlet; and (ii) a deformable membrane, said membrane being adapted to overlay said base and cooperate therewith to define a reservoir for containing a fluid, said reservoir being in communication with said first and second passageways of said base, said membrane being movable from first position to a second position; and (c) an expandable member disposed in contact with said deformable membrane for moving said membrane from said first position to said second position whereby the fluid contained within said reservoir will be urged to flow selectively into said first and second passageways of said base. 2. A device as defined in Claim 1 in which said additive presentation means comprises a structural support disposed within said container, said structural support having said additive removably carried thereby. 3. An apparatus as defined in Claim 1 in which said container assembly further includes first flow control means for controlling the flow of fluid through said fluid flow passageway of said container. 4. An apparatus as defined in Claim 3 in which said container includes second flow control means for controlling the flow of fluid through said fluid outlet of said base. 5. An apparatus as defined in Claim 4 in which said coupling means further includes operating means for operating said first flow control means. 6. An apparatus as defined in Claim 4 in which said base further includes an inlet port in communication with said reservoir. 7. A mixing apparatus comprising: (a) a container assembly including: (i) a first container having a fluid flow passageway and walls defining an internal chamber in communication with said fluid flow passageway; . (ii) adding means disposed within said chamber for adding an additive to fluid flowing through said chamber, said adding means comprising an additive and an additive presentation means for presenting said additive to the fluid; (b) a dispensing device comprising a housing having an outlet port and first and second portions, said first portion including: (i) coupling means for coupling said container assembly with said first portion of said housing, said coupling means having a first passageway adapted to communicate with said fluid flow passageway of said first container; (ii) flow control means for controlling the flow of fluid through said first passageway; said second portion comprising: (i) a base having first and second fluid passa¬ geways formed therein, said first passageway being in communication with said first passageway of said cou¬ pling means and said second passageway being in communication with said fluid outlet; (ii) a thin, generally planar deformable member, said member being adapted to overlay said base and cooperate therewith to define a reservoir for con¬ taining a fluid, said reservoir being in communica¬ tion with said first and second passageways of said base, said member being movable from a first position to a second position, whereby the fluid contained within said reservoir will be urged to flow into said first and second passageways of said base; and (c) an expandable member disposed in contact with said deformable member for moving said member toward said second position. 8. A device as defined in Claim 7 in which said expand¬ able member comprises an elastically deformable member having a cellular structure. 9. A device as defined in Claim 7 in which said expand¬ able member comprises a foamed polymer. 10. A device as defined in Claim 7 in which said expand¬ able member comprises a elastomer. 11. An apparatus as defined in Claim 7 in which said con¬ tainer assembly further comprises a second container having a chamber containing a liquid, said second container being adapt¬ ed to be coupled with said first container. 12. An apparatus as defined in Claim 11 in which said fluid flow passageway of said first container includes an inlet and an outlet and in which said coupling means includes a cannula disposed in communication with said first passageway of said base and in which said outlet of said fluid flow passage¬ way of said first container is closed by a first sealing member pierceable by said cannula upon coupling said container assem¬ bly with said first portion of said housing. 13. An apparatus as defined in Claim 12 in which said inlet of said fluid flow passageway of said first container is closed by a second sealing member and in which said second container includes a sealing assembly movable within said chamber thereof. 14. An apparatus as defined in Claim 12 in which said liquid in said chamber of said second container comprises a diluent. 15. An apparatus as defined in Claim 14 in which said additive comprises a medicament. 16. An apparatus as defined in Claim 14 in which said additive comprises a beneficial agent. 17. An apparatus as defined in Claim 16 in which said adding means comprises an additive which provides for extended release of a beneficial agent to the fluid over time. 18. A mixing and delivery apparatus comprising: (a) a container assembly including: (i) a container having a fluid flow passageway and walls defining an internal chamber in communica¬ tion with said fluid passageway; (ii) adding means disposed within said chamber for adding an additive to fluid flowing through said fluid flow passageway into said chamber, said adding means comprising an additive and an additive presen¬ tation means being disposed within said chamber in the path of fluid flowing into said chamber through said fluid flow passageway; and (b) a delivery device comprising a housing having first and second portions, said first portion including coupling means for coupling said container assembly with said first portion of said housing, said coupling means having a first passageway adapted to communicate with said fluid flow passageway of said container, said second portion of said housing comprising: (i) a base having a fluid outlet and first and second fluid passageways formed therein, said first passageway being in communication with said first passageway of said coupling means and said second passageway being in communication with said fluid outlet; and (ii) a thin, generally planar deformable mem¬ brane, said membrane being adapted to overlay said base and cooperate therewith to define a reservoir for containing a fluid, said reservoir being in communication with said first and second passageways of said base, said membrane being movable in a manner such that the fluid contained within said reservoir will be urged to flow selectively into said first and second passageways of said base; and (c) means comprising cellular structure for moving said deformable membrane. 19. An apparatus as defined in Claim 18 in which said additive comprise a biologically active material. 20. An apparatus as defined in Claim 18 in which said adding means comprises a polymer. 21. An apparatus as defined in Claim 18 in which said additive presentation means comprise a scaffold disposed within said container and adapted to releasably carry said additive. 22. An apparatus as defined in Claim 18 in which said additive is substantially removable from said additive presen¬ tation means using affinity chromotography techniques. 23. An apparatus as defined in Claim 22 including a ligand is connected to said support and a target molecule is connected to said ligand. 24. An apparatus as defined in Claim 23 in which a spacer arm is connected to said support and in which a ligand is con¬ nected to said spacer arm. 25. An apparatus as defined in Claim 24 in which and enzyme is connected to said target molecule. 26. An apparatus as defined in Claim 24 in which target molecule is a protein.

Inventors: KRIESEL MARSHALL S, THOMPSON THOMAS N, KRIESEL, MARSHALL, S., THOMPSON, THOMAS, N.
Applicants: KRIESEL MARSHALL S, SCIENCE INC, THOMPSON THOMAS N, KRIESEL, MARSHALL, S., SCIENCE INCORPORATED, THOMPSON, THOMAS, N.
Application year: 1994
Main classification: A61M37
IPC codes: A61M5, A61M37